What do the various form codes in U.S. Securities and Exchange Commission (SEC) filings represent?

My master’s thesis focused on U.S. equities, and I reviewed numerous SEC filings—so here’s a quick answer before dinner. In fact, the SEC’s official website provides detailed explanations of these forms. For full details, see: SEC.gov | Forms List Commonly encountered filing types include: F-1: Registration statement for initial public offerings by non-U.S. companies; S-1: Registration statement for initial public offerings by U.S. companies; POS AM: Post-effective amendment to a registration statement (e.g., correcting or updating prospectus information); 13D: Disclosure filed when an individual or group acquires beneficial ownership of more than 5% of a company’s equity securities; 144: Notice of proposed sale of securities under Rule 144; 20-F: Annual report or transition report filed by non-U.S. companies listed in the U.S.; ARS: Annual report to shareholders; 6-K: Current report filed by non-U.S. issuers; 10-Q: Quarterly report; 10-K: Annual report; 8-K: Current report disclosing material events or corporate changes occurring between quarterly reports; 11-K: Annual report covering employee stock purchase, savings, and similar plans; DEF 14A: Definitive proxy statement filed in connection with shareholder meetings. If needed, I can provide further explanations of commonly used forms.

Where can I find U.S. stock financial reports?

① The SEC’s official website: Its homepage features a search box—enter the stock ticker symbol, then locate filings labeled '10-K' for annual reports. Most recent filings are in HTML format; older ones may be in TXT format. ② Company websites: Look under the 'Investors' section—most firms maintain dedicated pages for annual reports. Upload timing varies by company—for example, Southwest Airlines posts reports dating back to 1971, whereas SkyWest only provides those from the post-millennium era. The above sources provide primary (original) documents. Secondary (repackaged) sources include financial data platforms such as Bloomberg and Wind (which definitely offer these reports); Wind has recently expanded its coverage significantly. Xueqiu (Snowball) also appears to host them. These platforms typically scrape SEC data and perform light processing before redistribution.

AdvanSix (ASIX) 10K Form and Latest SEC Filings 2026

2 days ago

AdvanSix Inc. has submitted over 394 SEC documents since 2017, including recent Form 4, 8-K, and 10-Q filings in 2026, providing regulatory updates for investors.

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